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NASA Orbital Debris Program Office at JSC has developed a computer-based orbital debris engineering model, ORDEM2000. The model describes the orbital debris environment in the low Earth orbit region between 200 and 2,000 km altitude. The model is appropriate for those engineering solutions requiring knowledge and estimates of the orbital debris environment (debris spatial density, flux, etc.). ORDEM2000 can also be used as a benchmark for ground-based debris measurements and
in the model is a large set of observational data (both in-situ and ground-based), covering the object size range from 10 µm to 10 m and employing a new analytical technique utilizing a maximum likelihood estimator to convert observations into debris population probability distribution functions. These functions then form the basis of debris populations. ORDEM2000 uses a finite element model to process the debris populations to form the debris environment. A more capable input and output structure and a user-friendly graphical user interface are also implemented in the model. ORDEM2000 has been subjected to a significant verification and validation effort. Currently, ORDEM2000 runs on Windows 95/98/2000/NT/XP computers.